Conventionally, technologies relating to step-up/down type power supply circuits that convert a DC input voltage into an arbitrary DC output voltage have been developed, for example, in order to suppress ripples of an output voltage, technologies for decreasing a peak-to-peak value of a current flowing through an inductance element and technologies for switching between a step-up operation and a step-down operation in accordance with a current flowing through an inductance element have been disclosed.
However, according to the conventional technologies, there is room for the improvement of an operation responding to an abrupt change in the load or the continuity at the time of switching between a step-down operation/a step-up/down operation/a step-up operation.